Daylight Savings Time

Snoopy seifert at hammer.UUCP
Tue Dec 3 08:49:56 AEST 1985


In article <1727 at uw-beaver> golde at uw-beaver.UUCP (Helmut golde) writes:

> I am unclear as to why *any* application program would ever want to know
> whether daylight savings time is in effect or not.

Example: date(1) needs to know.  Typical output from date:

Mon Dec  2 14:30:03 PST 1985
		    ^^^

Date needs to know if it is dst or not for printing out the date,
and also for setting the date, since it has to convert the
time given by root from local time to GMT before calling
settimeofday(2).

I have received two replys so far to my survey.  One said that he
prefers to use GMT for everything.  Fine, use "date -u".  (there doesn't
seem to be a option for ls -l to report in GMT. (no, ls -lu is
somthing different))  The other seemed to think that allowing users
to have their own timezone would mess up timestamps on files.
Not true.  Timestamps on files are stored as number of seconds
since 1/1/70 GMT, and the local timezone (system or user) has
nothing to do with it.  The only thing affected is what the user
sees when s/he runs date.

As far as what to do about the bozo congresscritters changing
the rules constantly, a solution would be to add a "manual"
type of daylight savings time, which would look for the
presence of a file to detirmine if it is dst or std.

Snoopy
tektronix!tekecs!doghouse.TEK!snoopy



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